Often we get customers calling the office and asking us what happened to their marble counter top. It looked great when it was first installed, but now they notice frosty rings on the surface. These are most often described as stains, but they are actually etch marks. We’ve enclosed a couple of pics to show you the size of a typical stain and how the stains look relative to reflective light. Because marble is composed of calcium carbonate (bones), it will react with acids and etch. A misunderstanding some people have is that sealing marble will protect against etch marks. This is not true. Etch marks are caused by the acid-calcium chemical reaction. Sealing protects against water and oil penetration. Designers should be aware that these types of stones-marble, limestone and travertine-will etch, especially when used in kitchens. Many homeowners with marble countertops hone their counters-a form of wet sanding- to give them a satin look. This is a much more forgiving finish than a high polish. Shiny countertops made of marble are not recommended in food areas for this very reason. You want to enjoy your kitchen counters, not worry about them, right?